Stacking machine



April 1953 R'. L. GRIFFIN 2,634,001

' STACKING MACHINE Filed Jan. 5, 1948 8 Sheets-Sheet 1 April 1953 R. L. GRIFFIN 2,634,001

STACKING MACHINE Filed Jan. 5, 1948 8 Sheets-Sheet 2 R: GRIFFIN STACKING MACHINE April 7, 1953 FiI Led Jan. 5, 1948 8 Sheets-Sheet 5 April 7, 1953 R. GRIFFIN STACKING MACHINE 8 Sheets-Sheet 4 Filed Jan. 5, 1948 .[Werzi'ar Kpril 7, 1953 R. L. GRI F'FIN 2,634,001

- STACKING MACHINE Filed Jan. 5, 1948 8 Sheets-Shet 5 R.. L. GRIFFIN STACKING MACHINE April 7, 1953 8 Sheets-Sheet '7 Filed Jan. 5, 194a QR %\M Patented Apr. 7, 1 953 STACKING MACHINE Roger L. Griffin, Marblehead, Mass, assignor, by

mesne assignments, to Swift & Company, Chi.- cago, 111., .a corporation of.Illinois Application January 3, 1948, Serial No. 403

.20 Claims.

This invention relates to a machine for stacking frames and the like relatively flat supporting members which, due to their size, shape, and/or weight, are difiicult to handle manually.

In the processing of leather and other types of sheet materials, particularly those of irregular shape, it is the practice to support the sheet material within a frame or on a relatively fiat board or the like surface and while thus supported to treat the exposed surface of the sheet material thereto. For example, in the manufacture of patent leather, the processed skins are stretched out and supported in stretched condition within the confines of a rectangular frame and while thus supported a coating of lacquer or other suitable finish is applied to the outer face, after which the frame is transferred to an oven where the coatingis dried in accordance with the requirements of the situation.

Although such coating may be applied manually, it is usually done while the frame is being conveyed beneath a battery of spray nozzles which traverse the entire surface of the skin, and provision must be made for receiving the frames as they are discharged from the conveyor, stacking them and transporting the stacks to the oven. Since such frames are usually of the'order of to square, manual handling would not only require the services of several employees, but also would be time-consuming, expensive and generally ineificient.

The principal object of the present invention is to provide a frame-stacking machine which is adapted to receive the frames and automatical 1y stack them so that the stack can readily be transported or conveyed to a drying oven or other desired location, as the case may be.

More specific objects are to provide a stacking machine which operates automatically in conjunction With a conveyor so as to receive the frames discharged therefrom, then stack a predetermined number of such frames and position the stacked frames for removal so that the stacking operation may be continued without interruption; and to provide control means for such a machine effective to arrest the operation of the stacking mechanism in the event a frame is not properly transported thereto or in the event a stack of frames is not removed from the machine after a predetermined period of operation.

Further objects relate to various features of construction and will be apparent from the consideration of the following description and accompanying drawings, wherein:

-Fig. 1 is a top plan view of a frame-stacking as by applying a coating composition or finish z machine constructed'in accordance with the present invention, but with certain parts of the framework, control switches, etc., removed to show the operating mechanisms more clearly;

Fig. 2 is a side elevation of the machine with certain parts removed;

Fig.3 is an enlarged vertical section on the line 3-3 of Fig. 1, showing the frame-lifting mechanism in elevated or uppermost position;

Fig. 4 is an enlarged vertical section on the line 4-4 of Fig. 1, showing the frame-lifting mechanism in lowermost position;

Fig. 5 is an enlarged vertical section on the line 55 of Fig. 1;

Fig. 6 is an isometric view of one of the lifting carriages;

Fig. '7 is a fragmentary top plan view of the upper right-hand corner of the machine as viewed in Figs. land 2;

Fig. 8 is a rear view of the counter mechanism and associated parts;

Fig. 9 is an enlarged section on the line 9-9 of Fig. 7;

Fig. 10 is a front view of the counter;

Fig. 11 is a side elevation showing the frame-lifting, frame-transfer and stacking-lifting mechanisms and associated operating mechanisms and controls therefor; I

Fig. 12 is a longitudinal section through the control valve; and

Fig. 13 is a wiring diagram of the electrical control system.

In accordance with the present invention the frame-stacking machine comprises a framework or other suitable structure defining an elevator well having at or adjacent its lower end an entrance opening to receive a frame or the like support and at or adjacent to its upper end a discharge opening through which a stack of frames may be removed. Between the entrance and discharge openings there is provided stationary supporting means for holding a stack of frames, and below the stack-supporting means is There is also provided a stack-lift-' 3 4 automatically operating a frame-lifting mechthe shafts 32 in one direction and then in the anism in response to the receipt of a frame to opposite direction. be stacked and there may also be provided con- The opposite ends of each of the shafts 32 trol means for effecting the operation of the carry a relatively large sprocket e juxtaposed stack-lifting mechanism after a predetermined 5 to a smaller sprocket 52 (Fig. 5) and vertically number of frames have been transferred to the aligned with each of the sprockets 5i! and 52 stack-supporting means, thereby permitting the are corresponding sprockets es and 56 rctatably stacking operation to continue without intermounted on stub shafts carried by pillow blocks ruption 58 which are supported on a pair of horizontal The accompanying drawings illustrate a stackl0 tructur l mem ers 60, 6|. The correspondi ing machine-designed for stacking rectangular vertically aligned p ts Carry chains 54 and frames carrying processed skins, such as patent 66 which are respectively connected with horileather, which have been conducted through a zontally aligned frame-lifting carria es 68 and spray-coating machine by a conveyor having its horizontally aligned frame-transfer carriages iii discharge end juxtaposed to the entrance open- (Figs.3 and 5).

ing of the stacking machine so that the con- Mounted n up ight channels 72 and 13 at a veyor discharges the frames directly into the level above the entrance open n E a fou stacking machine. In this particular embodipairs of stationary stack-supporting latch dogs ment the frames are to be stacked in groups of 14 a ed one at each side of the chains 64 twenty and after having built up a stack of and 66, as shown more clearly in Fig. 3. Each twenty frames, the stack-lifting mechanism is latch dog comprises n w r ly p j g fl t automatically brought into operation to elevate plate Shelf 75 integrally joined by a p of the stack to the level of the discharge opening Webs 75 130 sleeve p v ly ou ted on a so that another stack of twenty frames may be stud carried by a Sup-porting bracket 80 which built up without interruption. is fixed to one of the channels, as shown in Figs.

Referring to Figs. 1 to 4, the machine com- 3 d 5- An inward] r Will/lb} tiff 7 Fe a n iraswarm/[1mm wyWMWMlQ/WflM/W/ffi mam/00mm 0 1 2 1; 2 WWW fi ll WM it 0; W WWW/r r! WWW/it 5 mam/r I r a tit; ti l W W Mel/A a {UM/751W are 00519 1011 0 ppm g b a 6 0L 2 If M] WWII/6Q 01 y trar tHQ Heidi-limin f g or ggff' {g mggg m mm I Wen y ration to elevate 13 ivotally mounted on a iutomatically brought g Queuing Webs I9 to a sleeve;u prting bracket which the stack to the t 3; lfw nty frames may be g l g g g g hannels as s own in Figs. that another 8 25 1S Xe arm 82 b uilt up Without interi g g ijh machine cow 3 and amng 91 2 5; slgg gg g with an F sra. W1 ggg g g rggwor k of structural steel member gif 33 carried by the bracket at so as D tal llltlllfllnfi ertical channels I, 2 3 and 4 and normally to hold the Plate 15 m I a vertical lxlnsversell and longltudmaly extenllll Iwrl position projecting g the path of 1 ins llwlapgl. 11161 WW ncfllmfill f l I {/l mo w '1 wil it Am I .6. -The inneredge of the plates 90 and iii are .recessed-above the shelf .98 so as to permit the 'latch dog tabeswung upwardly out "of the path of travel .of a frame F.

With this construction and arrangement of .parts the four frame-lifting carriages move in .unison from-their lowermost or frame-receiving position (shown in the full lines of Fig. 5 and the broken lines of Fig. 11) to elevated or frametransfer position (shown in the full lines of Fig. 11), .and simultaneously the four frametransfer carriages I move downwardly. As the 'carriages'fiil pass the carriages 10, the latch dogs of .the latter are swung upwardly by the engagement with the sides of the frame F supported on the carriages 58, after which the latch dogs swing back to :normal position, thus completing the first half cycle of the frame-lifting andframetransferring operation. During the second half cycle the carriages 58 move downwardly while the carriages I0 move upwardly and as the carriages pass each other the frame supported by the carriages fit'is transferred to the carriages I0 which elevate it to a level above the stationary dogs 14, as shown in Figs. 4 and 5. During this half cycle the sides of the frame F swing the .stationarydogs I4 upwardly and afterpassing by the dogs, the latter drop back to a normal position. After completion of the second half cycle the firstframe transferred to the carriages 1:0 istemporarilyheld in elevated position above the levelof the stationary latch dogs I4, as shown in v-l5ig.- 5, but during the next half cycle theframe-transfercarriages Iii-descend and thus transfer the frame F to the stationary dogs,

after which the carriages. I0 pick up another frame from the carriages 68. As the second frame F-Z (Fig. 11) is being lifted it engages the firstframe F-I previously transferred to'the stationary or stack-supporting dogs I4 and both frames F-I and F-.'Z are lifted by the carriages I0 andtemporarily supported at the uppermost level of the carriages I0, The next downward movement of the carriages I0 (second half cycle) transfers .both frames to the stationary dogs I4,

after which .aithird' frame F'3 is picked up by and transferred. from th frame-lifting carriages 68, and the operation is repeated until the desired number of frames have been transferred and stacked.

The frame-lifting and transfer mechanisms are actuated by the piston 43 within the cylinder 44, as previously explained, and the operation of the piston is automatically controlled by a valve system (Fig. 11) including a three-way valve H0, suitably mounted at the rear of the framework with its operating arm or lever HI positioned to be engaged by the leading edge of 'theframe F as it approaches the end of the elevator well, as indicated in Figs. 4 and 11. One branch. of the valve III! is connected with an air .s'upplyiline H2, thesecond branch is connected by a line I I4 with oneport of a control valve I I5 (Figs. .11 and 12) and the third branehlprovides an exhaust I I6 to the atmosphere. 1

Another three-way valve I .is suitably secured 'tothelframework with its operating arm or lever I2! juxtaposed tothe face of. the sprocket 3? so as to be engaged by a pin I22 projecting therefrom whenthe piston 43 approaches the end of its first stroke. Onebranch of the valve .tween the line I30 and the line MI.

and the third branch provides an exhaust I20 to-the atmosphere. One end of a line I30 is connected-bye. T :I3I with the air supply line H2 and its opposite-end is connected to'a third port of control valve I I5.

The control valve II5 (Fig. 12) comprises a cylinder having at opposite ends ports to which the lines H4 and I25 are connected, a central port .to which -:the line I is connected and which communicates with an internal annular groove-l34, exhaust ports I and I36 at each sideof the central port and ports I3! and I38 diametrically opposite ports I35 and I36,respec tively. The ports I-3Iand I38 are connected by lines I40 and I4I,"respectively, to the opposite ends of the cylinder 44. A piston valve member I42 is slidable within the cylinder I I5 and adjacent 'to each end the-piston is formed with annular grooves I44 and I45, and between the groovesI44 and I is a longitudinally extending groove I45.

The construction and arrangement of parts are-such that when thevalve member I42 i in one position, as shown in Fig. 12, the groove I44 provides a communication betweenports I35 and I3! and the groove I43 provides a connection be- Hence, air in the supplyline I I I2 may flow through the line I30, grooves I34 and I46 and port I38into'the line -I4I which conducts it to one end of the cylinder, therebyeffecting'movement of the piston to one end of the cylinder, asshown in Fig. 11. The air displaced by such movement is conducted through the line I40, groove I44 and outexhaust portI3-5. When the valve member I42 moves to the other end of the cylin'denport I35 is closed and the groove I45 provides a communication between line I4I and exhaust port I36, and grooves I34 and I46 provide a communicat-ion between the line I30 and the line I40, thus transferring the air supply to the opposite end of the cylinder 44 and thereby effecting movement of the-piston 43 back to its first position, the air displaced by the return movement of thepiston being exhausted through line I4I, groove I45 and port 136.

The movement of the valve member I42 and 'hence the operation of the piston 43 is controlled by the-operation .ofvalves H0 and I20, it being noted that when a frame F trips lever III, the

valve H0 connects supply line II2with line II4,

thus causing'valve member I42 totravel toward one end of the cylinder to initiate the first half cycle, and as the'first half cycle is about to be completed, the pin' I 22 trips the lever I2I of valve I20 to connect supply line IIZ with the line I25, thus causing valve member M2 to travel toward the opposite end of the cylinder II5 to initiate the second half cycle.

Mounted at the front or receiving end of the framework just below-the entrance opening E is anormally closed switch S4 (Figs. 3 and 11) having its operating arm positioned so as to be :engagedand thus opened by the leading edge of aiframe F. as it entersthe elevator well. and a corresponding position at the rear of the frameworkis anothernormally closed switch S3 (Fig.

4) having its operating "arm positioned to be engaged andthus opened. by-the leading edge of the frame F as it approaches the end of the elevator welhin which position the trailing edge of the frame F disengages the operating arm of switch S4 thus closing the switch. With the frame properly positioned within the elevator well, v the switch vS4.ren'1ains closed .but switch S3 -riages 68, whereupon the switch S3 closes.

7 is held open until the frame is lifted by the car- The two switches are connected in a circuit, hereinafter described, which controls the operation of the conveyor motor CM (Fig. 13) and the stacklifting mechanism.

The stack of frames F transferred to the stacksupporting dogs It! is periodically elevated by a stack-lifting mechanism I50 (Figs. 2, 3 and 11) the operation of which is controlled by a counter mechanism I52 (Figs. '7-10) actuated by the frame-lifting mechanism. The counter mechanism IE2 is mounted on a base plate I54 supported by the horizontal frame members 69 and SI and comprises a shaft I55 rotatably mounted in pillow blocks I59 and II. The outer end of the shaft I55 carries a pointer I69 cooperating with a dial IfiI fixed to the base I54, and the inner end of the shaft carries a ratchet wheel I62 having twenty notches. A ratchet lever I64 is rotatably mounted on the inner end of the shaft I55 and pivotally mounted on this lever is a pawl I55 yieldingly held in operative engagement with the teeth of the ratchet wheel by a small tension spring 559, as shown in Fig. 8. The outer end of the lever I64 carries a laterally projecting pin I98 engageable with a lug I19 carried by the adjacent chain run 54, the construction and arrangement of parts being such that as the carriages 88 return from their uppermost position the lug I'III engages the pin I58 to swing lever I65 through an angle sufficient to advance the ratchet wheel I92 one notch. A small leaf spring I72 is secured to a bracket I mounted on the base I54 with its free end engaging the teeth of the ratchet wheel I62, as shown in Fig. 8, to prevent back travel.

Mounted between the pillow blocks I56 and I5! are upstanding brackets I14 and I15 which support a normally open switch SI and a normally closed switch S6, respectively, both of which have inwardly extending actuating levers I16 and Ill offset with respect to each other, as shown more clearly in Fig. 9. Mounted on the shaft I55 in alignment with the levers I16 and III are operating arms I89 and IBI arranged so that the arm I89 closes switch SI when the twentieth frame F has been transferred, but opens the switch SI when the next frame has been transferred, and the arm IBI opens switch S6 when the eighteenth frame has been transferred, but closes the switch S6 when the nineteenth frame has been transferred. With this construction and arrangement of parts, the descending movement of chains 94 effecting the transfer of a frame F from carriages 58 to carriages i9 operates the counter mechanism I52 and when the eighteenth frame has been transferred, switch S6 opens and remains open until the nineteenth frame has been transferred (for reasons hereinafter to be pointed out), and when the twentieth frame has been transferred SI closes to operate the stacklifting mechanism I59 presently to be described.

The stack-lifting mechanism I comprises two pairs of vertically aligned shafts I99 and II carried by pillow blocks mounted on the upright channels I I at the corners of the elevator well W. The lower shafts I99 are horizontally aligned at a level slightly below that of the stationary dogs I5 and the upper shafts I99 are horizontally aligned at a level slightlyabove the lower part of the discharge opening D, as shown in Figs. 2, 3, and 11. Adjacent to their opposite ends the shafts I99 and I9! carry sprockets, I94 and I95, respectively, and chains I96 and'l9l extend about each pair of sprockets.

At equally spaced portions chains I96 and I9! support the ends of transversely extending T-bars I98 which are so positioned as to engage and lift a stack of frames supported on the stationary dogs 15 when the sprockets are rotated. Juxtaposed to and extending between the inner faces of the sprockets are guide bars 299 which prevent the frames in the stack from becoming displaced as the stack is being lifted to elevated position (Fig. 2).

The upper shafts I9l also carry driving sprockets 292 and 204 which are respectively connected by chains 295 and 296 with speed reducers 298 and '2I9 (Fig. 2) connected to a common drive shaft 2l2 which carries a sheave 2M. This sheave is equipped with a backstop to prevent reverse travel under the weight of the stack of frames and is driven by a motor 2 I5 controlled by the switch SI. With this construction and arrangement the motor drives the sprocket 292 clockwise and the sprocket 254 counterclockwise, as viewed in Fig. 2.

Mounted on the upright channel 3 (Figs. 4 and 11) is a normally closed switch S2 having its operating lever positioned to be engaged and thus opened by one of the T-bars I98 as it is carried downwardly to the level of the lower shaft I99, as shown more clearly in Fig. 4. The switch S2 is connected in the control circuit (Fig. 13) of switch SI and is operative to shut off motor 255 when the stack of frames has been elevated to the level of discharge opening D. Mounted at the upper end of the channel 3 is a normally closed switch S5 having its operating lever arranged to be engaged and thus opened by the uppermost frame of the stack lifted by the T-bars I98. The switch S5 is connected in the control circuit, hereinafter described, along with the switches S3, S4 and S6.

In normal operation the transfer of the twentieth frame closes the switch SI and effects operation of the stack-lifting motor 2I5, whereupon sprockets I94 and I95 are rotated so as to elevate the stack-lifting bars I98 which raise the stack of twenty frames from the stationary dogs I4 to the level of discharge opening D, in which position a fork truck may remove them to an oven or other location, as previously explained. At the beginning of this operating cycle, the lower T-bar I98 disengages the operating lever of switch S2, thus closing the circuit to the motor 2I5 and as the switch SI remains closed until another frame has been elevated by the carriages 68, the circuit to the motor remains closed. When the lifting bars I98 carrying the stack of frames reaches the level of the discharge opening D, switch S5 is opened and in the meantime the other lifting bar I98 has traveled downwardly to a position wherein it operates switch S2 to open the motor circuit, thus shutting off the motor as hereinafter more fully explained. The stack of frames is now supported at the level of the discharge opening and reverse travel of the stack is prevented by the backstop associated with sheave 2M. Switch S5 remains open until the fork truck has removed the stack, after which it automatically closes.

Referring to Fig. 13, the control circuits for the stack-lifting mechanism and the conveyor motor CM operating the conveyor C are interconnected with each other as shown, it being noted that the power circuit is a three-phase system having the usual lines :0, y and 2 connected through a solenoid-operated switch 225 with the conveyor motor CM and through a second sole- 9' noid-operated switch 226 with the stack-lifting motor 2| 5. One of the" terminals of the solenoid 230 of 'switch'225 is connected with the line 1. and the other terminal isconnected to a line in-which the normally closed-switches S3 to S6 are connected in series-parallel. This line is connected in series with the stop button23l and the'start button 232 which have the conventional connections with the power line. De-

pressing the start button closes the circuitthrough thesolenoid 230 which actuates switch rod 234- to' closethe power circuit to conveyor motor CM; provided that the proper'combination of switches S3 to S6 remain closed, in which case themotor CMis' put into operation.

The switch 226 includes the usualsolenoid 236- which operates switch rod 238 and one terminal of this solenoid is connected to the power line :11 and the other terminal to a branched circuit 240, one branch of which is connected through switchSZ' in the-usual-manner to thepower line. The other branch is connected with a conventional time-delay relay 242 (e. g. a G; E. type CR 7504) which includes the usual normally closed switch S1 in series with the normally open switch-SI whichis connected in the usual manner to thepower line. The switch Sland associatedpartsare so designed that the switch S1 opens-after a period of-- six to eight seconds and is not closed untilswitch 'Sl has been opened to reset the relay.

Whenthe switch SI is closed by the transfer ofthe twentieth frame, as above explained; the

circuit through the solenoid 236 is closed andhence'closesthe power line-to motor 215, whereupon the stack of frames is elevated. After six to eight seconds from the time the switch SI is closed the switch S7 opens to cut the circuit through the switch SI, but prior to the expiration of the sixto eight second period, the stacklifting motor 215 has operated long enough to causethe lower bar I98 to disengage the operating. lever of switch S2, which thereupon closes, thus..-maintaining the circuit through the solenoid. 2.315. closed. When the stack has been elevated: to: the level of the discharge opening D,

switchSZJopens and remains open until the next stack-lifting. operation commences.- Hence, after completing the stack-lifting operation, switches SZand ST remain open, thus breaking the circuit through the solenoid236 andstopping the motor H5.. The transfer of the next frame received from the conveyor operates the counter mechanism so as to open switch SI and when the twentieth frame of the next group is transferred, switch SI closes, and as the relay has now been reset, switch S1 is again closed for a period of six. to. eight seconds durin which period the above describedv operation is repeated.

A rsum of. the operation of the machine is as follows:

A frame F is received from the spray conveyor C and rides on driven rolls 22- which travel at a greater speed than the spray conveyor to pull the frame away from the latter. Upon entering the well W, the frame opens switch S4 which closes when the frame has been carried 'to the end of the well, at which time its leading edge engages the valve lever III of air valve Hi! and the operating lever. of switch S3 at the rear of the well. Actuation of the valve H0 operates control valve H5, thereby causing a single stroke (half cycle) of the piston 43.

The. piston 43: operates through .its connecting rod 42 and associated chain 40. to rotate the sprockets 36and 31 clockwise (Fig; 11) and thus rotate shafts 32 and 33 so as to cause the lifting carriages 58 to ride upwardly about twenty inches to lift the frame F slightly above the level of the dogs of the transfer carriages 10 which have been carried downwardly to their lowermost position below the level of stationary dogs 14.

When .the piston'43 reaches the end of its forward' stroke, the pin I22 carried by sprocket 37 engages the arm l2! of the valve lit which operates the control valve H5 to. admit air pressure to the other end of the cylinder, thereby causing the piston :13 to return to' its original position; The return movement of the piston causes the sprockets and operating shafts to rotate clockwise (Fig. 11) thereby lowering the frame-lifting. carriages :68 and elevating the transfer carriages 1!]. As the frame-lifting carriage is lowered, it transfers theframe to the carriages 1!] which elevate it, together with the frames previously received and temporarily held on the fixed dogs 14, to a position above the latter, thereby completing the operating cycle. As the frame-lifting chain 64 returns to its lowermost position, the lug I it carried thereby operates the counter mechanism I52.

The foregoing operating cycle is repeated twenty times and when the twentieth frame is transferred to'the lowstack, switch S1 closes the solenoid-operated switch 226 which starts the elevator motor 2L5, as above explained. When the stack reaches its top position the switch S2 opens=the magnetic switch226 to stop the-motor zld thetime relay 242 being effective to preventiovertravel incase switch SI were held closed after. the switchSZ had been opened. The stack of twenty frames supported on the T-bars I98 isethus elevated andmade ready to be picked up by the forktruck. The switch S5 is held open by the. stack and. automatically closes when the stack is removed. 'In the event a frame discharged fromthe sprayconveyor C is not transferred'to the stack; the switch Se isopenedby an. incomingv frame and the switch S3 is held opened bythe: frame which was not. transferred.

Hence, as. both switches S30 and S4 are open,

the: circuit to-the conveyor-motor CM is broken and hence the conveyor. motor is stopped and the. power lines to motor 2l5 is broken. The

trouble may then berectified and normal opera-- tion resumed.

In the event the elevated stack isnet timely removed. by thefork truck, the switch S5-rema-ins open and switch S6 (associated with the counter) opens after the. eighteenth frame ofthe low stack is transferred tothe stacking dog I4. If the upper stack is removedby the fork truck, S5 necessarily closes, but if not removed S5 remains open and when S6 opens the circuit to conveyor motor CM is broken and hence the operation of the spray conveyor is stopped as is also the elevator'motor 215. Before the machine can resume normal operation, the elevatedstack of frames must be removed by the fork truck,

thereby closing switch S5 which permits the.

energized and the power circuit to the motor 215 remains open. The switches S2 and S1 remain.

open until the normal stacking operation is resumed, as above explained.

While I have shown and described one desirable embodiment of the invention it is to be understood that this disclosure is for the purpose of illustration and that various modifications may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

I claim:

' l. A machine for stacking frames and the like articles, comprising stationary upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stack-supporting means for holding a stack of frames at a level between the entrance and discharge openings, frame-lifting mechanism for elevating a frame received through the entrance opening and transferring it to said stack-supporting means, and a stacklifting mechanism operative to elevate a stack of frames held by said stack-supporting means to a level within said elevator well at which it may be withdrawn through said discharge opening, said stack-lifting mechanism being operative to support said stack of frames at the last-mentioned level, thereby to permit operation of said frame-lifting mechanism to form another stack.

2. A machine for stacking frames and the like articles, comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stack-supporting means for holding a stack of frames at a level between the entrance and discharge openings, frame-lifting mechanism for elevating a frame received through the entrance opening and transferring it to said stacksupporting means, a stack-lifting mechanism operative to elevate a stack of frames held by said stack-supporting means to a level at which they may be withdrawn through said discharge.

opening;

last-mentioned level, thereby to permit operation of said frame-lifting mechanism to form another stack, control mechanism operative to actuate said frame-lifting and transferring mechanism When a frame is properly positioned within said well, and contro1 mechanism operative when a predetermined number of frames have been transferred to said stack-supporting means to actuate said stack-lifting mechanism.

3. A machine for stacking frames and the like articles comprising stationary upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stack-lifting mechanism for elevating a stack of frames within said elevator well from a level above that of said entrance opening to the level of said discharge opening, and framelifting and transferrin mechanism for elevating a frame received through said entrance opening and transferring it to said stack-lifting mechanism, said stack-lifting mechanism being operative to support said stack of frames at the level of said discharge opening, thereby to permit said stack-lifting mechanism being operative to support said stack of frames at the operation of said frame-lifting and transferring mechanism to form another stack.

4. A machine for stacking frames and the like stack of frames from a level above that of said entrance opening to the level of said dischargeopening, mechanism for elevating a frame received through said entrance opening and transferring it to said stack-lifting mechanism, said stacklifting mechanism being operative to support said stack of frames at the level of said discharge opening, thereby to permit operation of said frame-lifting and transferring mechanism to to form another stack, conveying mechanism for delivering individual frames through said entrance opening, and control mechanism operative to actuate said frame-lifting and transferring mechanism in response to the delivery of a frame through said entrance opening.

5. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings,

frame-lifting mechanism for elevating a frame received through said entrance opening to a level below said stationary latch dogs, frametransferring mechanism vertically movable from a lowermost position, wherein it receives a frame elevated by said frame-lifting mechanism, to an uppermost position, wherein it transfers a frame to said stationary latch dogs, and stack-lifting mechanism for elevating a stack of frames supported by said stationary latch dogs to the level of said discharge opening, said stack-lifting mechanism being operative to support said stack of frames at the last-mentioned level, thereby to permit operation of said frame-lifting mechanism to form another stack.

6. A machine for stacking frames and the like articles comprising upright members defining an elevator well havin adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings, frame-lifting mechanism for elevating a frame received through said entrance opening to a level below said stationary latch dogs, frametransferring mechanism vertically movable from a lowermost position, wherein it receives a frame elevated by said frame-lifting mechanism, to an uppermost position, wherein it transfers a frame to said stationary latch dogs, stack-lifting mechanism for periodically elevating a stack of frames supported by said stationary latch dogs to the level of said discharge opening, said stacklifting mechanism being operative to support said stack of frames at the last-mentioned level, thereby to permit operation of said frame-lifting mechanism to form another stack, conveying mechanism for delivering individual frames through said entrance opening, and means efiecand frame-lifting and transferring- 13 tive upon delivery of aframe: through said entrance opening to operate said frame-lifting mechanism and frame-transferring mechanism.

7. A machine for stackingframes and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for Supporting a stack of frames at a level between the entrance and: discharge openings, frame-lifting mechanismfor elevating a frame received through said entrance opening to a level below said stationary latch dogs, frame-transferring mechanism vertically: movable from a lowermost position, wherein it receives a frame elevated by said frame-lifting mechanism, to an uppermost position, wherein it transfers a frame to said stationary latch dogs, stack-lifting mechanism for periodically elevating a stack: of frames supported by said stationary latch dogs to the level of said discharge opening, said stack-lifting mechanism being operative to support said stack of frames at the lastmentioned level, thereby to permit operation of said frame-lifting mechanism to form another stack, control mechanism operative to actuate said frame-lifting mechanism when a frame is properly positioned. within said well, and means operative after the transferring of a frame to said frame-transferring mechanism for effecting the operation of the latter mechanism.

8. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end adischarge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings, frame-lifting mechanism for elevating a frame received through said entrance opening to a level below said stationary latch dogs, frametransferring mechanism vertically movable from a lowermost position, wherein it receives a frame elevated by said frame-lifting mechanism, to an uppermost position, wherein it transfers a frame to said stationary latch dogs, stack-lifting mechanism for elevating a stack of frames supported by said stationary latch dogs to the level of said discharge opening, said stack-lifting mechanism bein operative to support said stack of frames at a the last-mentioned level, thereby to permit operation of said frame-lifting mechanism to form another stack, control mechanism operative to actuate said frame-lifting mechanism when a frame is properly positioned within said well, means operative after the transferring of a, frame to said frame-transferring mechanism for effecting the operation of the latter mechanism, and control 14 openings, latch dogs-vertically movable. from a lowermost frame-receiving position to an uppermost position below said stationary latch dogs and back to the first position, transfer mechanism including latch dogs vertically movable from an uppermost position above the level of said stationary latch dogs to a lowermost position below the uppermost position of the latch dogs of said frame-lifting mechanism and back to the first level above said stationary dogs so that upon downward movement of saidframe-transferring mechanism the frame carried thereby is transferred to'said stationary dogs.

10. Amachine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings. frame-lifting mechanism including latch dogs vertically movable froma lowermost frame-receiving position toan uppermost position below said stationary latch dogs and back to the first position, transfer mechanism including latch dogs vertically movable from an uppermost position above the level of said stationary latch dogs to a lowermost position below the uppermost position of the latch dogs of said frame-lifting mechanism and back to the first position, connections between said frame-lifting mechanism and transfer mechanism operative to lower said transfer mechanism as said frame-lifting mechanism moves upwardly thereby to effect the transfer of a frame carried thereby, and to elevate said frame-transferring mechanism as said frame-lifting mechanism moves downwardly,

thereby to position the frame at a level above said stationary dogs so that upon downward movement of said frame-transferring mechanism the frame carried thereby is transferred to said stationary dogs, and stack-lifting mechanism operative tolift a stack of frame transferred to said stationary dogs to the level of said discharge openings.

11. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to it upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings, frame-lifting mechanism including latch dogs vertically movable from a lowermost frame-receiving position to an uppermost position below said stationary latch dogs and back to the first position, transfer mechanism including latch dogs vertically movable from an uppermost position above the level of said stationary latch dogs to a lowermost position below the uppermost position of the latch dogs of said frame-lifting mechanism and back to the first position, connections between said frame-lifting mechanism frame-lifting mechanism including and transfer mechanism operative to lower said transfer mechanism as said frame-lifting mechanism moves upwardly thereby to effect the transfer of a frame carried thereby, and to elevate said frame-transferring mechanism as said frame-lifting mechanism moves downwardly, thereby to position the frame at a level above said stationary dogs so that upon downward movement of said frame-transferring mechanism the frame carried'thereby is transferred to said stationary dogs, and stack-lifting mechanism operative after a predetermined number of frames have been transferred to said stationary dogs to lift the stacks of frames to the level of said discharged openings.

12. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame, stationary latch dogs carried by said upright members for supporting a stack of frames at a level above said entrance opening, frame-lifting mechanism including latch dogs vertically movable from a lowermost frame-receiving position to an uppermost position below said stationary latch dogs and back to the first position, transfer mechanism including latch dogs vertically movable from an uppermost position above the level of said stationary latch dogs to a lowermost position below the uppermost position of the latch dogs of said frame-lifting mechanism and back to the first position, connections between said framelifting mechanism and transfer mechanism operative to lower said transfer mechanism as said frame-lifting mechanism moves upwardly thereby to effect the transfer of a frame carried thereby, and to elevate said frame-transferring mechanism as said frame-lifting mechanism moves downwardly, thereby to position the frame at a level above said stationary dogs so that upon downward movement of said frame-transferring mechanism the frame carried thereby is transferred to said stationary dogs, conveying mechanism for delivering individual frames through said entrance openings, and mechanism for automatically operating said frame-lifting and said frame-transferring mechanisms in response to the delivery of a frame through said entrance opening. n

'13. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame, stationary latch dogs carried by said upright members for supporting a stack of frames at a level above said entrance opening, a plurality of pairs of interconnected vertically movable, oppositely travelling reciprocating members, the corresponding members of each pair of having frame-lifting latch dogs movable from a lowermost position in which they receive a frame delivered through said entrance opening to an uppermost position below said stationary latch dogs, the other corresponding members of each pair having frametransfer latch dogs movable from an uppermost position above said stationary latch dogs to a lowermost position below the uppermost position of said frame-lifting latch dogs, the upward movement of said frame-transfer latch dogs being effective to transfer a frame carried by said frame-lifting latch dogs to said frame-transfer latch dogs and the subsequent downward movement of said frame-transfer latch dogs being effective to transfer the frame carried by said frame-lifting latch dogs to said frame-transfer latch dogs and the subsequent downward movement of saidframe-transfer latch dogs being ef'- fective to transfer the frame carried thereby to said stationary latch dogs.

14. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings, a plurality of pairs of interconnected vertically movable oppositely travelling reciprocating members, the corresponding members of each pair having frame-lifting latch dogs movable from a lowermost position in which they receive a frame delivered through said entrance opening to an uppermost position below said stationary latch dogs, the other corresponding members of each pair having frame-transfer latch dogs movable from an uppermost position above said stationary latch dogs to a lowermost position below the uppermost position of said frame-lifting latch dogs, the upward movement of said frame-transfer latch dogs being effective to transfer a frame carried by said frame-lifting latch dogs to said frame-transfer latch dogs and the subsequent downward movement of said frame-transfer latch dogs being effective to transfer the frame carried by said frame-lifting latch dogs to said frame-transfer latch dogs and the subsequent downward movement of said frametransfer latch dogs being effective to transfer the frame carried thereby to said stationary latch dogs, and stack lifting mechanism operative to elevate a stack of frames supported by said stationary latch dogs to the level of said discharge opening.

15. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame, stationary latch dogs carried by said upright members for supporting a stack of frames at a level above said entrance opening, a plurality of pairs of vertically movable oppositely travelling, reciprocating chains, one chain of each pair carrying frame-lifting latch dogs movable from a lowermost position in which they receive a frame delivered through said entrance opening to an uppermost position below said stationary latch dogs, the other chain of each pair carrying frame-transfer latch dogs movable from an uppermost position above said stationary latch dogs to a lowermost position below the uppermost position of said frame-lifting latch dogs, the upward movement of said frame-transfer latch dogs being effective to transfer a frame carried by said frame-lifting latch dogs to said frame-transfer latch dogs and the subsequent downward movement of said frame-transfer latch clogs being effective to transfer the frame carried thereby to said stationary latch dogs.

16. A machine for stacking frames and the like articles comprising upright members defining an elevator Well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings, a plurality of pairs of vertically movable oppositely travelling, reciprocating chains,

one chain of each pair carrying frame-lifting latch dogs movable from a lowermost position in which they receive a frame delivered through said entrance opening to an uppermost position below said stationary latch dogs, the other chain of each pair carrying frame-transfer latch dogs movable from an uppermost position above said stationary latch dogs to a lowermost position below the uppermost position of said framelifting latch dogs, the upward movement of said frame-transfer latch dogs being effective to transfer a frame carried by said frame-lifting latch dogs to said frame-transfer latch dogs and the subsequent downward movement of said frame-transfer latch dogs being effective to transfer the frame carried thereby to said stationary latch dogs, and stack-lifting mechanism operative after a predetermined number of frames have been transferred to said stationary latch dog-s to elevate the stack of frames supported thereby to the level of said discharge opening.

17. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame, stationary latch dogs carried by said upright members for supporting a stack of frames at a level above said entrance opening, frame lifting mechanism comprising horizontal shafts mounted in vertically aligned pairs adjacent to opposite ends of said well above and below said entrance opening, a pair of relatively large sprockets carried by opposite ends of each shaft and a pair of relatively small sprockets carried by the opposite ends of each shaft, the large sprockets being arranged in vertically aligned pairs and the small sprockets being arranged in vertically aligned pairs juxtaposed to the large sprockets, vertically disposed chains extending about each pair of large and small sprockets, the chains associated with the large sprockets carrying horizontally aligned frame-lifting latch dogs arranged to engage the marginal portions of the under surface of the frame received through said entrance opening so as to lift the frame to an uppermost position slightly below the level of said stationary latch dogs when said shafts are rotated in one direction, the chains associated with the smaller sprockets carrying horizontally aligned frametransfer latch dogs arranged to travel from an uppermost position slightly above said stationary latch dogs to a lowermost position slightly below the uppermost position ofv said frame-lifting latch dogs when said shafts are rotated in said one direction and from the latter position back to the former position when said shafts are rotated in the opposite direction, thereby to effect the transfer of a frame from said frame-lifting latch dogs to said stationary latch dogs, and motor mechanism for effecting a predetermined rotationof said shafts in one direction and then in the other direction.

18. A machine for stacking frames and the like articles comprising upright members defining an elevator well having adjacent to its lower end an entrance opening to receive a frame and adjacent to its upper end a discharge opening through which a stack of frames may be withdrawn, stationary latch dogs carried by said upright members for supporting a stack of frames at a level between the entrance and discharge openings, frame-lifting mechanism comprising horizontal shafts mounted in vertically aligned pairs of adjacent to opposite ends of said well above and below said entrance opening, a pair of relatively large sprockets carried by opposite ends of each shaft and a pair of relatively small sprockets carried by the opposite ends of each shaft, the large sprockets being arranged in vertically aligned pairs and the small sprockets being arranged in vertically aligned pairs juxtaposed to the large sprockets, vertically disposed chains extending about each pair of large and small sprockets, the chains associated with the large sprockets carrying horizontally aligned frame-lifting latch dogs arranged to engage the marginal portions of the under surface of the frame received through said entrance opening so as to lift the frame to an uppermost position slightly below the level of said stationary latch dogs when said shafts are rotated in one direction, the chains associated with the smaller sprockets carrying horizontally aligned frametransferring latch dogs arranged to travel from an uppermost position slightly above said stationary latch dogs to a lowermost position slightly below the uppermost position of said frame-lifting latch dogs when said shafts are rotated in said one direction and from the latter position back to the former position when said shafts are rotated in the opposite direction, thereby to effect the transfer of a frame from said frame-lifting latch dogs to said stationary latch dogs, motor mechanism for effecting a predetermined rotation of said shafts in one direction and then in the other direction, and stacklifting mechanism for elevating a stack of frames supported by said stationary latch dogs to the level of said discharge opening.

19. A stacking machine as set forth in claim 1, which includes control mechanism associated with the frame-lifting mechanism and operative to arrest the operation of said frame-lifting mechanism in event a frame supported thereby is not transferred to the stack-supporting means.

20. A stacking machine as set forth in claim 1, which includes control mechanism associated with the frame-lifting and stack-lifting mechanisms and operative t arrest their operations in event a stack of elevated frames is not removed through the discharge opening after a predetermined period of operation of said mechanisms.

ROGER L; GRIFFIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,292,636 Parker Jan. 28, 1919 1,689,332 Eaton Oct. 30, 1928 1,789,917 Tomlinson Jan. 20,1931 2,313,478 Neja Mar. 9, 1943 2,329,413 Neja Sept. 14, 1943 

